Forty years ago, the Organization of the Petroleum Exporting Countries placed an embargo on petroleum, bringing an oil-addled world to its knees. As oil prices quadrupled, the world panicked. In the immediate aftermath, gas stations closed on Sundays. Small, fuel-efficient cars became popular. And Brazil -- a developing country under military dictatorship at the time -- began the push for what has become the most successful biofuel industry in the world.